org.apache.xmlbeans
Interface XmlCursor

Represents a position between two logical tokens in an XML document.
The tokens themselves are not exposed as objects, but their type and properties
are discoverable through methods on the cursor. In particular, the general
category of token is represented by a TokenType.

You use an XmlCursor instance to navigate through and manipulate an XML
instance document.
Once you obtain an XML document, you can create a cursor to represent
a specific place in the XML. Because you can use a cursor with or
without a schema corresponding to the XML, cursors are an ideal
way to handle XML without a schema. You can create a new cursor by
calling the newCursor method
exposed by an object representing
the XML, whether it was parsed into a strong type compiled from
schema or an XmlObject (as in the no-schema case).

With an XmlCursor, you can also:

Execute XQuery and XPath expressions against the XML with the
execQuery and selectPath methods.

Edit and reshape the document by inserting, moving, copying, and removing
XML.

Insert bookmarks that "stick" to the XML at the cursor's
position even if the cursor or XML moves.

Get and set values for containers (elements and whole documents),
attributes, processing instructions, and comments.

A cursor moves through XML by moving past tokens. A
token represents a category of XML markup, such as the start of an element,
its end, an attribute, comment, and so on. XmlCursor methods such as
toNextToken, toNextSibling, toParent, and so on move the cursor
among tokens. Each token's category is of a particular type, represented
by one of the nine types defined by the TokenType class.

When you get a new cursor for a whole instance document, the cursor is
intially located before the STARTDOC token. This token, which has no analogy
in the XML specification, is present in this logical model of XML
so that you may distinguish between the document as a whole
and the content of the document. Terminating the document is an ENDDOC
token. This token is also not part of the XML specification. A cursor
located immediately before this token is at the very end of the document.
It is not possible to position the cursor after the ENDDOC token.
Thus, the STARTDOC and ENDDOC tokens are effectively "bookends" for the content of
the document.

For example, for the following XML, if you were the navigate a cursor
through the XML document using toNextToken(), the list of token types that
follows represents the token sequence you would encounter.

When there are no more tokens available, hasNextToken() returns
false and toNextToken() returns the special token type NONE and does not move
the cursor.

The currentTokenType() method
will return the type of the token that is immediately after the cursor.
You can also use a number of convenience methods that test for a particular
token type. These include the methods isStart(),
isStartdoc(), isText(), isAttr(), and so on. Each returns a boolean
value indicating whether the token that follows the cursor is the type
in question.

A few other methods determine whether the token is of a kind that may include
multiple token types. The isAnyAttr() method, for example, returns true if
the token immediately following the cursor is any kind of attribute,
including those of the ATTR token type and xmlns attributes.

Legitimate sequences of tokens for an XML document are described
by the following Backus-Naur Form (BNF):

getChars()
Returns characters to the right of the cursor up to the next token.

int

getChars(char[] returnedChars,
int offset,
int maxCharacterCount)
Copies characters up to the specified maximum number, counting right from
this cursor's location to the character at maxCharacterCount.

getTextValue()
Gets the text value of the current document, element, attribute,
comment, procinst or text token.

int

getTextValue(char[] returnedChars,
int offset,
int maxCharacterCount)
Copies the text value of the current document, element, attribute,
comment, processing instruction or text token, counting right from
this cursor's location up to maxCharacterCount,
and copies the returned text into returnedChars.

insertAttributeWithValue(String name,
String uri,
String value)
Inserts an attribute immediately before the cursor's location, giving it
the specified name and value, and associating it with the specified namespace.

insertElement(String localName)
Inserts an element immediately before this cursor's location, giving
the element the specified local name.

void

insertElement(String localName,
String uri)
Inserts a new element immediately before this cursor's location, giving the
element the specified local name and associating it with specified namespace

void

insertElementWithText(QName name,
String text)
Inserts a new element immediately before this cursor's location, giving the
element the specified qualified name and content.

void

insertElementWithText(String localName,
String text)
Inserts a new element immediately before this cursor's location, giving the
element the specified local name and content.

void

insertElementWithText(String localName,
String uri,
String text)
Inserts a new element immediately before this cursor's location, giving the
element the specified local name, associating it with the specified namespace,
and giving it the specified content.

void

insertNamespace(String prefix,
String namespace)
Inserts a namespace declaration immediately before the cursor's location,
giving it the specified prefix and URI.

setTextValue(char[] sourceChars,
int offset,
int length)
Sets the text value of the XML at this cursor's location (if that XML's
token type is START, STARTDOC, ATTR, COMMENT or PROCINST) to the
contents of the specified character array.

void

setTextValue(String text)
Sets the text value of the XML at this cursor's location if that XML's
token type is START, STARTDOC, ATTR, COMMENT or PROCINST.

dispose

void dispose()

Deallocates resources needed to manage the cursor, rendering this cursor
inoperable. Because cursors are managed by a mechanism which stores the
XML, simply letting a cursor go out of scope and having the garbage collector
attempt to reclaim it may not produce desirable performance.

So, explicitly disposing a cursor allows the underlying implementation
to release its responsibility of maintaining its position.

After a cursor has been disposed, it may not be used again. It can
throw IllegalStateException or NullPointerException if used after
disposal.

pop

selectPath

Executes the specified XPath expression against the XML that this
cursor is in. The cursor's position does not change. To navigate to the
selections, use hasNextSelection() and toNextSelection() (similar to
Iterator).

The root referred to by the expression should be given as
a dot. The following is an example path expression:

selectPath

Executes the specified XPath expression against the XML that this
cursor is in. The cursor's position does not change. To navigate to the
selections, use hasNextSelection and toNextSelection (similar to
java.util.Iterator).

The root referred to by the expression should be given as
a dot. The following is an example path expression:

toSelection

boolean toSelection(int i)

Moves this cursor to the specified location in the selection.
If i is less than zero or greater than or equal to the selection
count, this method returns false.
See also the selectPath() and addToSelection() methods.

Parameters:

i - The index of the desired location.

Returns:

true if the cursor was moved; otherwise, false.

getSelectionCount

int getSelectionCount()

Returns the count of the current selection. See also the selectPath()
and addToSelection() methods.
You may experience better performance if you use the iteration
model using the toNextSelection method, rather than
the indexing model using the getSelectionCount and
toSelection methods.

Returns:

A number indicating the size of the current selection.

addToSelection

void addToSelection()

Appends the current location of the cursor to the selection.
See also the selectPath() method. You can use this as an
alternative to calling the selectPath method when you want
to define your own selection.

clearSelections

void clearSelections()

Clears this cursor's selection, but does not modify the document.

toBookmark

Moves this cursor to the same position as the bookmark. If the
bookmark is in a different document from this cursor or if the
bookmark is orphaned, this cursor
will not be moved, and false will be returned.

Parameters:

bookmark - The bookmark at the location to which this
cursor should be moved.

getName

Returns the name of the current token. Names may be associated with
START, ATTR, NAMESPACE or PROCINST. Returns null if there is no
name associated with the current token. For START and ATTR, the
name returned identifies the name of the element or attribute.
For NAMESPACE, the local part of the name is the prefix, while
the URI is the namespace defined. For PROCINST, the local part
is the target and the uri is "".

In the following example, xmlObject represents
an XML instance whose root element is not preceded by any other XML.
This code prints the root element name (here, the local name, or
name without URI).

namespaceForPrefix

Returns the namespace URI indicated by the given prefix. The current
context must be at a START or STARTDOC. Namespace prefix mappings
are queried for the mappings defined at the current container first,
then parents are queried. The prefix can be "" or null to indicate
a search for the default namespace. To conform with the
XML spec, the default namespace will return the no-namespace ("")
if it is not mapped.

Note that this queries the current state of the document. When the
document is persisted, the saving mechanism may synthesize namespaces
(ns1, ns2, and so on) for the purposes of persistence. These namepaces are
only present in the serialized form, and are not reflected back into
the document being saved.

Parameters:

prefix - The namespace prefix for the requested namespace.

Returns:

The URI for corresponding to the specified prefix if it
exists; otherwise, null.

prefixForNamespace

Returns a prefix that can be used to indicate a namespace URI. The
current context must be at a START or STARTDOC. If there is an
existing prefix that indicates the URI in the current context, that
prefix may be returned. Otherwise, a new prefix for the URI will be
defined by adding an xmlns attribute to the current container or a
parent container.
Note that this queries the current state of the document. When the
document is persisted, the saving mechanism may synthesize namespaces
(ns1, ns2, and so on) for the purposes of persistence. These namepaces are
only present in the serialized form, and are not reflected back into
the document being saved.

Parameters:

namespaceURI - The namespace URI corresponding to the requested
prefix.

Returns:

The prefix corresponding to the specified URI if it exists;
otherwise, a newly generated prefix.

currentTokenType

Returns the type of the current token. By definition, the current
token is the token immediately to the right of the cursor.
If you're in the middle of text, before a character, you get TEXT.
You can't dive into the text of an ATTR, COMMENT or PROCINST.

As an alternative, it may be more convenient for you to use one of the
methods that test for a particular token type. These include the methods
isStart(), isStartdoc(), isText(), isAttr(), and so on. Each returns a boolean
value indicating whether the token that follows the cursor is the type
in question.

Returns:

The TokenType instance for the token at the cursor's current
location.

isStartdoc

boolean isStartdoc()

True if the current token is a STARTDOC token type, meaning
at the very root of the document.

Returns:

true if this token is a STARTDOC token type;
otherwise, false.

isEnddoc

boolean isEnddoc()

True if this token is an ENDDOC token type, meaning
at the very end of the document.

Returns:

true if this token is an ENDDOC token type;
otherwise, false.

isStart

boolean isStart()

True if this token is a START token type, meaning
just before an element's start.

Returns:

true if this token is a START token type;
otherwise, false.

isEnd

boolean isEnd()

True if this token is an END token type, meaning
just before an element's end.

Returns:

true if this token is an END token type;
otherwise, false.

isText

boolean isText()

True if the this token is a TEXT token type, meaning
just before or inside text.

Returns:

true if this token is a TEXT token type;
otherwise, false.

isAttr

boolean isAttr()

True if this token is an ATTR token type, meaning
just before an attribute.

Returns:

true if this token is an ATTR token type;
otherwise, false.

isNamespace

boolean isNamespace()

True if this token is a NAMESPACE token type, meaning
just before a namespace declaration.

Returns:

true if this token is a NAMESPACE token type;
otherwise, false.

isComment

boolean isComment()

True if this token is a COMMENT token type, meaning
just before a comment.

Returns:

true if this token is a COMMENT token type;
otherwise, false.

isProcinst

boolean isProcinst()

True if this token is a PROCINST token type, meaning
just before a processing instruction.

Returns:

true if this token is a PROCINST token type;
otherwise, false.

isContainer

boolean isContainer()

True if this token is a container token. The STARTDOC and START
token types are containers. Containers, including documents and elements,
have the same content model. In other words, a document and an element
may have the same contents. For example, a document may contain attributes
or text, without any child elements.

Returns:

true if this token is a container token; otherwise, false.

isFinish

boolean isFinish()

True if this token is a finish token. A finish token can be an ENDDOC
or END token type.

Returns:

true if this token is a finish token; otherwise, false.

isAnyAttr

boolean isAnyAttr()

True if this token is any attribute. This includes an ATTR token type and
the NAMESPACE token type attribute.

toNextToken

Moves the cursor to the next token. When there are no more tokens
available, hasNextToken returns false and toNextToken() returns
NONE and does not move the cursor. Returns the token type
of the token to the right of the cursor upon a successful move.

Returns:

The token type for the next token if the cursor was moved;
otherwise, NONE.

toEndToken

Moves the cursor to the END or ENDDOC token corresponding to the
current START or STARTDOC, and returns END or ENDDOC.

If the current token is not a START or STARTDOC, the cursor is not
moved and NONE is returned.

Returns:

The new current token type.

toNextChar

int toNextChar(int maxCharacterCount)

Moves the cursor forward by the specified number of characters, and
stops at the next non-TEXT token. Returns the number of characters
actually moved across, which is guaranteed to be less than or equal to
maxCharacterCount. If there is no further text, or if
there is no text at all, returns zero.

Note this does not dive into attribute values, comment contents,
processing instruction contents, etc., but only content text.

You can pass maxCharacterCount < 0 to move over all the text to the
right. This has the same effect as toNextToken, but returns the amount
of text moved over.

Parameters:

maxCharacterCount - The maximum number of characters by which
the cursor should be moved.

Returns:

The actual number of characters by which the cursor was moved;
0 if the cursor was not moved.

toPrevChar

int toPrevChar(int maxCharacterCount)

Moves the cursor backwards by the number of characters given. Has
similar characteristics to the toNextChar method.

Parameters:

maxCharacterCount - The maximum number of characters by which
the cursor should be moved.

Returns:

The actual number of characters by which the cursor was moved;
0 if the cursor was not moved.

toNextSibling

boolean toNextSibling()

Moves the cursor to the next sibling element, or returns
false and does not move the cursor if there is no next sibling
element. (By definition the position of an element is the same
as the position of its START token.)
If the current token is not s START, the cursor will be
moved to the next START without moving out of the scope of the
current element.

Returns:

true if the cursor was moved; otherwise, false.

toPrevSibling

boolean toPrevSibling()

Moves the cursor to the previous sibling element, or returns
false and does not move the cursor if there is no previous sibling
element. (By definition the position of an element is the same
as the position of its START token.)

Returns:

true if the cursor was moved; otherwise, false.

toParent

boolean toParent()

Moves the cursor to the parent element or STARTDOC, or returns
false and does not move the cursor if there is no parent.

Works if you're in attributes or content. Returns false only if at
STARTDOC. Note that the parent of an END token is the corresponding
START token.

Returns:

true if the cursor was moved; false if the cursor is at the STARTDOC
token.

toFirstChild

boolean toFirstChild()

Moves the cursor to the first child element, or returns false and
does not move the cursor if there are no element children.

If the cursor is not currently in an element, it moves into the
first child element of the next element.

Returns:

true if the cursor was moved; otherwise, false.

toLastChild

boolean toLastChild()

Moves the cursor to the last element child, or returns false and
does not move the cursor if there are no element children.

toNextSibling

Moves the cursor to the next sibling element of the specified
qualified name.

Parameters:

name - The name of the element to move the cursor to.

Returns:

true if the cursor was moved; otherwise, false.

toFirstAttribute

boolean toFirstAttribute()

Moves the cursor to the first attribute of this element, or
returns false and does not move the cursor if there are no
attributes. The order of attributes is arbitrary, but stable.

If the cursor is on a STARTDOC of a document-fragment, this method will
move it to the first top level attribute if one exists.
xmlns attributes (namespace declarations) are not considered
attributes by this function.

The cursor must be on a START or STARTDOC (in the case of a
document fragment with top level attributes) for this method to
succeed.
Example for looping through attributes:

XmlCursor cursor = ... //cursor on START or STARTDOC
if (cursor.toFirstAttribute())
{
do
{
// do something using attribute's name and value
cursor.getName();
cursor.getTextValue();
}
while (cursor.toNextAttribute());
}

Returns:

true if the cursor was moved; otherwise, false.

toLastAttribute

boolean toLastAttribute()

Moves the cursor to the last attribute of this element, or
returns false and does not move the cursor if there are no
attributes. The order of attributes is arbitrary, but stable.

xmlns attributes (namespace declarations) are not considered
attributes by this function.

The cursor must be on a START or STARTDOC for this method
to succeed.

Returns:

true if the cursor was moved; otherwise, false.

toNextAttribute

boolean toNextAttribute()

Moves the cursor to the next sibling attribute, or returns
false and does not move the cursor if there is no next
sibling attribute. The order of attributes is arbitrary, but stable.

xmlns attributes (namespace declarations) are not considered
attributes by this function.

getTextValue

Gets the text value of the current document, element, attribute,
comment, procinst or text token.

When getting the text value of an element, non-text content such
as comments and processing instructions are ignored and text is concatenated.
For elements that have nested element children, this
returns the concatenated text of all mixed content and the
text of all the element children, recursing in first-to-last
depthfirst order.

For attributes, including namespaces, this returns the attribute value.

For comments and processing instructions, this returns the text content
of the comment or PI, not including the delimiting sequences <!-- -->, <? ?>.
For a PI, the name of the PI is also not included.

getTextValue

Copies the text value of the current document, element, attribute,
comment, processing instruction or text token, counting right from
this cursor's location up to maxCharacterCount,
and copies the returned text into returnedChars.

When getting the text value of an element, non-text content such
as comments and processing instructions are ignored and text is concatenated.
For elements that have nested element children, this
returns the concatenated text of all mixed content and the
text of all the element children, recursing in first-to-last
depthfirst order.

For attributes, including namespaces, this returns the attribute value.

For comments and processing instructions, this returns the text contents
of the comment or PI, not including the delimiting sequences <!-- -->, <? ?>. For
a PI, the text will not include the name of the PI.

getChars

getChars

int getChars(char[] returnedChars,
int offset,
int maxCharacterCount)

Copies characters up to the specified maximum number, counting right from
this cursor's location to the character at maxCharacterCount. The
returned characters are added to returnedChars, with the first
character copied to the offset position. The maxCharacterCount
parameter should be less than or equal to the length of returnedChars
minus offset. Copies a number of characters, which is
either maxCharacterCount or the number of characters up to the next token,
whichever is less.

Parameters:

returnedChars - A character array to hold the returned characters.

offset - The position within returnedChars at which the first of the
returned characters should be added.

maxCharacterCount - The maximum number of characters after this cursor's
location to return.

Returns:

The actual number of characters returned; 0 if no characters
were returned or if the current token is not TEXT.

toStartDoc

void toStartDoc()

Moves the cursor to the STARTDOC token, which is the
root of the document.

toEndDoc

void toEndDoc()

Moves the cursor to the ENDDOC token, which is the end
of the document.

comparePosition

Returns an integer indicating whether this cursor is before,
after, or at the same position as the specified cursor.

a.comparePosition(b) < 0 means a is to the left of b.a.comparePosition(b) == 0 means a is at the same position as b.a.comparePosition(b) > 0 means a is to the right of b.

The sort order of cursors in the document is the token order.
For example, if cursor "a" is at a START token and the cursor "b"
is at a token within the contents of the same element, then
a.comparePosition(b) will return -1, meaning that the position
of a is before b.

Parameters:

cursor - The cursor whose position should be compared
with this cursor.

Returns:

1 if this cursor is after the specified cursor; 0 if
this cursor is at the same position as the specified cursor;
-1 if this cursor is before the specified cursor.

setBookmark

Sets a bookmark to the document at this cursor's location.
The bookmark is attached to the token in the tree immediately
after the cursor. If the tree is manipulated to move
that object to a different place, the bookmark moves with it.
If the tree is manipulated to delete that token from the
tree, the bookmark is orphaned. Copy operations do not copy
bookmarks.

Parameters:

bookmark - The bookmark to set.

getBookmark

Retrieves the bookmark with the specified key
at this cursor's location. If there is no bookmark whose key is
given by the specified key at the current position, null is returned.
If the getKey method is not overridden on
the bookmark, then the bookmark's class is used as the key.

Parameters:

key - The key for the bookmark to retrieve.

Returns:

The requested bookmark; null if there is no bookmark
corresponding to the specified key.

getAllBookmarkRefs

Retrieves all the bookmarks at this location, adding them to
the specified collection. Bookmarks held by weak references are
added to this collection as Weak referenced objects pointing to the
bookmark.

Parameters:

listToFill - The collection that will contain bookmarks
returned by this method.

removeXml

boolean removeXml()

Removes the XML that is immediately after this cursor.
For the TEXT, ATTR, NAMESPACE, COMMENT and PROCINST tokens, a single
token is removed. For a START token, the corresponding element and all
of its contents are removed. For all other tokens, this is a no-op.
You cannot remove a STARTDOC.
The cursors located in the XML that was removed all collapse to the
same location. All bookmarks in this XML will be orphaned.

Returns:

true if anything was removed; false only if the cursor is
just before END or ENDDOC token.

moveXml

Moves the XML immediately after this cursor to the location
specified by the toHere cursor, shifting XML at that location
to the right to make room. For the TEXT, ATTR, NAMESPACE,
COMMENT and PROCINST tokens, a single token is moved. For a start token, the
element and all of its contents are moved. For all other tokens, this
is a no-op.
The bookmarks located in the XML that was moved also move to the
new location; the cursors don't move with the content.

Parameters:

toHere - The cursor at the location to which the XML should
be moved.

Returns:

true if anything was moved. This only happens when the XML to be
moved contains the target of the move.

Throws:

IllegalArgumentException - If the operation is not allowed
at the cursor's location. This includes attempting to move an end token or the
document as a whole. Also, moving to a location before the start document or moving
an attribute to a location other than after another attribute or start token
will throw.

copyXml

Copies the XML immediately after this cursor to the location
specified by the toHere cursor. For the TEXT, ATTR, NAMESPACE,
COMMENT and PROCINST tokens, a single token is copied. For a start token,
the element and all of its contents are copied. For all other tokens, this
is a no-op.
The cursors and bookmarks located in the XML that was copied are also copied
to the new location.

Parameters:

toHere - The cursor at the location to which the XML should
be copied.

Returns:

true if anything was copied; false if the token supports the operation,
but nothing was copied.

moveXmlContents

Moves the contents of the container (STARTDOC OR START) immediately after
this cursor to the location specified by the toHere cursor.
For all other situations, returns false. Does not move attributes or
namespaces.

Parameters:

toHere - The cursor at the location to which the XML should be moved.

Returns:

true if anything was moved; otherwise, false.

copyXmlContents

Copies the contents of the container (STARTDOC OR START) immediately to
the right of the cursor to the location specified by the toHere cursor.
For all other situations, returns false. Does not copy attributes or
namespaces.

Parameters:

toHere - The cursor at the location to which the XML should
be copied.

Returns:

true if anything was copied; otherwise, false.

removeChars

int removeChars(int maxCharacterCount)

Removes characters up to the specified maximum number, counting right from
this cursor's location to the character at maxCharacterCount. The
space remaining from removing the characters collapses up to this cursor.

Parameters:

maxCharacterCount - The maximum number of characters after this cursor's
location to remove.

moveChars

Moves characters immediately after this cursor to the position immediately
after the specified cursor. Characters are counted to the right up to the
specified maximum number. XML after the destination cursor is
shifted to the right to make room. The space remaining from moving the
characters collapses up to this cursor.

Parameters:

maxCharacterCount - The maximum number of characters after this cursor's
location to move.

copyChars

Copies characters to the position immediately after the specified cursor.
Characters are counted to the right up to the specified maximum number.
XML after the destination cursor is shifted to the right to make room.

Parameters:

maxCharacterCount - The maximum number of characters after this cursor's
location to copy.

beginElement

Inserts a new element around this cursor, giving the element the specified
qualified name. After the element is inserted, this cursor is between its start
and end. This cursor can then be used to insert additional XML into
the new element.

beginElement

Inserts a new element around this cursor, giving the element the specified
local name. After the element is inserted, this cursor is between its start
and end. This cursor can then be used to insert additional XML into
the new element.

beginElement

Inserts a new element around this cursor, giving the element the specified
local name and associating it with the specified namespace. After the element
is inserted, this cursor is between its start and end. This cursor
can then be used to insert additional XML into the new element.